Should I put the new engine in or buy a new vehicle?

I have been having engine problems with my 2005 f150 with only 100k miles after hitting a helmet that fell off a motorcycle on the highway. My insurance will not cover it because they are claiming that this is a problem with ford engines in a certain range of years. They are telling me that there isn't any conclusive evidence that says the helmet caused all these problems. Well I took the truck to a two mechanics and both mechanics say I need to buy a new engine (old one I will eventually have the same problems with) and they are saying they will put a new engine in for $8,400. This is no doubt a lot of money to put into my truck. I bought it just over a year ago for $14,000. I need to know if putting the engine in it is worth it or what should I do?

The helmet didn't cause the problem. I would go with a re-built engine, w/ warranty! MOST F150s DON't go out with only 100,000 miles! I've been a mechanic for over 50 years!

No, I seriously doubt that all your engine troubles came from hitting a motorcycle helmet in the road.

I also doubt that it's not worth $8,400 for a NEW engine in your truck… But, there's no real need for a complete NEW engine. There are several options, from a USED engine from an auto salvage yard, to a new short block to a completely rebuilt engine from a local auto machine shop.

Check around and find out what the different options will cost.

Well lets look at the numbers $14,000 truck a year ago, $8,400 for a NEW engine.
NOT a good deal at all, convert this truck to electric www.EpicCarConversions.com throw a few more bucks is and get something reliable.
Why would you want to go back to a gas vehicle which will give you another $8400 bill?
What I would do,
Shop around for another mechanic, put in a used an Engine from an accident vehicle from the scrap yard.
FIX your existing engine, what is the problem, can it be repaired for substantially less?
Make the truck electric!

You state you have taken it to two mechanics so I'm assuming the truck is running you also state you had this problem after hitting a helmet. It makes me feel like you have bent the oil pan in and it is hitting on the crank throw which would make a sound like a rod knock when it is not. Just me thinking.

WHICH ENGINE is it? I would be totally AMAZED if the WHOLE engine filed! They had issues with SPARK PLUGS in cylinder heads that require a special tool to remove to prevent damage to threads and head alloys! They NEVER had any issues with the engine block itself and $8400 is RIDICULOUS! Try car-part.com for GOOD used engine in your area, but REALIZE that real issues are usually confined to the CYLIDNER HEADS! They CAN be repaired or replaced CHEAPLY! ASK AT FORD DEALERSHIP which engines suffered from this issue! This is NOT the 70's or 80's when things were MUCh cheaper to own and fix, but there's a HUGE profit margin in that inflated $8400 price tag! VERY HUGE!

All Ford Vehicles have problems with rusty rotten oil pans.